This invention relates to a metal-air cell, particularly a metal-air cell with a catalytic electrode having a catalytic mixture including a carbon-catalyst composite material, a method of manufacturing the catalytic electrode, and a method of manufacturing the cell.
Metal-air cells have a negative electrode that includes a metal that is oxidized upon discharge of the cell and a positive electrode that reduces oxygen entering from outside the cell. The positive electrode is a catalytic electrode that can include a catalyst for the oxygen reduction reaction and an electrically conductive material such as carbon. In some cells the catalytic electrode includes a carbon-catalyst composite material. Manganese oxides are often used as the catalyst in the carbon-catalyst composite. It serves to catalyze the reduction of peroxides formed from the reduction of oxygen, while the carbon provides both reaction sites for the reduction of oxygen and an electrically conductive matrix in the electrode.
There is an ongoing need to increase the discharge capability of metal-air cells to meet the ever-increasing levels of current and power for electrical devices powered by these battery types, as well as to reduce the cell to cell variation in electrical performance. It is desirable to provide improvements in cell electrical performance with minimal increase in the cell manufacturing processes and costs.